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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 69| Part 11| November 2013| Pages o1603-o1604

2-Allyl-7-nitro-2H-indazole

aLaboratoire de Chimie Organique et Analytique, Université Sultan Moulay Slimane, Faculté des Sciences et Techniques, Béni-Mellal, BP 523, Morocco, bDipartimento di Chimica 'G. Ciamician', Università degli Studi di Bologna, Via Selmi 2, I-40126 Bologna, Italy, and cLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: assoman_k@yahoo.fr

(Received 24 September 2013; accepted 28 September 2013; online 2 October 2013)

The asymmetric unit of the title compound, C10H9N3O2, contains two independent mol­ecules linked by a C—H⋯N hydrogen bond. Each mol­ecule has a similar conformation, being built up from fused five- and six-membered rings, each linked to an ally and nitro group, respectively. The indazole ring system makes dihedral angles of 2.7 (2) and 2.2 (2)°, respectively, with the plane through the nitro group. The allyl group is nearly perpendicular to the indazole system, as indicated by the N—N—C—C torsion angles of −75.3 (2) and −82.2 (2)°, this being the most important difference between the conformations of the two mol­ecules. In the crystal, mol­ecules are linked by C—H⋯O and ππ [inter-centroid distance = 3.6225 (8) Å] inter­actions to form a three-dimensional network.

Related literature

For pharmacological effects of indazole derivatives, see: Baraldi et al. (2001[Baraldi, P. G., Balbonic, G., Pavani, M. G., Spalluto, G., Tabrizi, M. A., Clercq, E. D., Balzarini, J., Bando, T., Sugiyama, H. & Romagnoli, R. (2001). J. Med. Chem. 44, 2536-2543.]); Li et al. (2003[Li, X., Chu, S., Feher, V. A., Khalili, M., Nie, Z., Margosiak, S., Nikulin, V., Levin, J., Sparankle, K. G., Fedder, M. E., Almassy, R., Appelt, K. & Yager, K. M. (2003). J. Med. Chem. 46, 5663-5673.]); Lee et al. (2001[Lee, F.-Y., Lien, J.-C., Huang, L.-J., Huang, T.-M., Tsai, S.-C., Teng, C.-M., Wu, C.-C., Cheng, F.-C. & Kuo, S.-C. (2001). J. Med. Chem. 44, 3746-3749.]); Rodgers et al. (1996[Rodgers, J. D., Johnson, B. L., Wang, H., Greenberg, R. A., Erickson-Viitanen, S., Klabe, R. M., Cordova, B. C., Rayer, M. M., Lam, G. N. & Chang, C. H. (1996). Bioorg. Med. Chem. Lett. 6, 2919-2924.]); Schmidt et al. (2008[Schmidt, A., Beutler, A. & Snovydovych, B. (2008). Eur. J. Org. Chem. pp. 4073-4095.]). For similar compounds, see: El Brahmi et al. (2012[El Brahmi, N., Benchidmi, M., Essassi, E. M., Ladeira, S. & El Ammari, L. (2012). Acta Cryst. E68, o3368.]); Chicha et al. (2013[Chicha, H., Rakib, E. M., Spinelli, D., Saadi, M. & El Ammari, L. (2013). Acta Cryst. E69, o1410.]).

[Scheme 1]

Experimental

Crystal data
  • C10H9N3O2

  • Mr = 203.20

  • Triclinic, [P \overline 1]

  • a = 8.1848 (3) Å

  • b = 8.3253 (4) Å

  • c = 16.3194 (6) Å

  • α = 84.168 (2)°

  • β = 85.653 (2)°

  • γ = 60.843 (2)°

  • V = 965.64 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.42 × 0.29 × 0.17 mm

Data collection
  • Bruker X8 APEX diffractometer

  • 22310 measured reflections

  • 4980 independent reflections

  • 4107 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.142

  • S = 1.04

  • 4980 reflections

  • 271 parameters

  • H-atom parameters constrained

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10A⋯N2 0.93 2.60 2.907 (3) 100
C5—H5⋯O1i 0.93 2.49 3.4004 (19) 165
C8—H8A⋯O4ii 0.97 2.45 3.205 (2) 134
C15—H15⋯O4i 0.93 2.49 3.3986 (19) 167
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The indazole subunit in organic molecules is an important structure in many drug substances with a wide range of pharmacological effects: e.g., anti-tumor, anti-microbial, anti-platelet, anti-HIV, and anti-inflammatory (Baraldi et al., 2001; Li et al., 2003; Lee et al., 2001; Rodgers et al., 1996; Schmidt et al., 2008). The present work is a continuation of the investigation of the indazole derivatives published recently by our team (El Brahmi et al., 2012; Chicha et al., 2013).

The plot of the structure of the title compound, with two molecules in the asymmetric unit, shows them linked by a C8—H8B···N4 hydrogen bond, Fig. 1. In the molecules, the allyl groups are nearly perpendicular to indazole planes as indicated by the torsion angles of C8–C9–N1–N2 = -75.3 (2)° and C18–C19–N4–N5 = -82.2 (2)°. This is the most important difference between the two conformations of the molecules as shown in the overlay diagram of the two crystallographically independent molecules (Fig. 2). The dihedral angles of 2.7 (2) and 2.2 (2)°, respectively, between the fused ring systems and the nitro groups lead to a synperiplanar conformation for each molecule.

In the crystal, molecules are linked by C—H···O (Table 2) and ππ [inter-centroid distances between centrosymmetrically related (C1–C6) rings = 3.6225 (8) Å; symmetry operation = 1-x, 1-y, 1-z] interactions, forming a three-dimensional network.

Related literature top

For pharmacological effects of indazole derivatives, see: Baraldi et al. (2001); Li et al. (2003); Lee et al. (2001); Rodgers et al. (1996); Schmidt et al. (2008). For similar compounds, see: El Brahmi et al. (2012); Chicha et al. (2013).

Experimental top

To a solution of 7-nitroindazole (6.13 mmol) in acetone (15 ml) was added potassium hydroxide (6.8 mmol). After 15 min. at 298 K, allyl bromide (12.26 mmol) was added drop wise. Upon disappearance of the starting material as indicated by TLC, the resulting mixture was evaporated. The crude material was dissolved with EtOAc (50 ml), washed with water and brine, dried over MgSO4 and the solvent was evaporated in vacuo. The resulting residue was purified by column chromatography (EtOAc/hexane 3/7). The title compound was recrystallized from ethanol at room temperature giving colorless crystals (m.p. 358 (1) K, yield: 65%).

Refinement top

H atoms were located in a difference map and treated as riding with C—H = 0.93–0.97 Å, and with Uiso(H) = 1.2Ueq.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: APEX2 (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The two molecules comprising the asymmetric unit of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small circles.
[Figure 2] Fig. 2. Overlay diagram of the two crystallographically independent molecules highlighting the different orientations of the allyl groups.
2-Allyl-7-nitro-2H-indazole top
Crystal data top
C10H9N3O2Z = 4
Mr = 203.20F(000) = 424
Triclinic, P1Dx = 1.398 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.1848 (3) ÅCell parameters from 4980 reflections
b = 8.3253 (4) Åθ = 2.5–28.7°
c = 16.3194 (6) ŵ = 0.10 mm1
α = 84.168 (2)°T = 296 K
β = 85.653 (2)°Irregular shape, colourless
γ = 60.843 (2)°0.42 × 0.29 × 0.17 mm
V = 965.64 (7) Å3
Data collection top
Bruker X8 APEX
diffractometer
4107 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.028
Graphite monochromatorθmax = 28.7°, θmin = 2.5°
ϕ and ω scansh = 1111
22310 measured reflectionsk = 1111
4980 independent reflectionsl = 2222
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.142H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.076P)2 + 0.1973P]
where P = (Fo2 + 2Fc2)/3
4980 reflections(Δ/σ)max = 0.001
271 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.24 e Å3
Crystal data top
C10H9N3O2γ = 60.843 (2)°
Mr = 203.20V = 965.64 (7) Å3
Triclinic, P1Z = 4
a = 8.1848 (3) ÅMo Kα radiation
b = 8.3253 (4) ŵ = 0.10 mm1
c = 16.3194 (6) ÅT = 296 K
α = 84.168 (2)°0.42 × 0.29 × 0.17 mm
β = 85.653 (2)°
Data collection top
Bruker X8 APEX
diffractometer
4107 reflections with I > 2σ(I)
22310 measured reflectionsRint = 0.028
4980 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.142H-atom parameters constrained
S = 1.04Δρmax = 0.37 e Å3
4980 reflectionsΔρmin = 0.24 e Å3
271 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against all reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on all data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.40636 (16)0.52858 (16)0.63233 (7)0.0352 (2)
C20.32039 (17)0.46916 (16)0.57894 (7)0.0365 (3)
C30.22059 (19)0.58263 (18)0.51389 (8)0.0439 (3)
H30.16560.54130.47950.053*
C40.1994 (2)0.76114 (19)0.49786 (9)0.0506 (3)
H40.12970.83630.45340.061*
C50.2794 (2)0.82492 (18)0.54647 (9)0.0491 (3)
H50.26590.94250.53540.059*
C60.38287 (18)0.71050 (17)0.61358 (8)0.0406 (3)
C70.4834 (2)0.7291 (2)0.67340 (9)0.0478 (3)
H70.49780.83140.67920.057*
C80.6739 (2)0.5268 (3)0.79150 (9)0.0568 (4)
H8A0.62890.47180.83660.068*
H8B0.66060.64040.80920.068*
C90.8763 (2)0.3989 (3)0.77569 (10)0.0595 (4)
H90.95680.38300.81680.071*
C100.9523 (3)0.3085 (3)0.71208 (12)0.0699 (5)
H10A0.87860.31910.66900.084*
H10B1.08120.23210.70890.084*
N10.51163 (16)0.44398 (16)0.69883 (7)0.0424 (3)
N20.55488 (16)0.57195 (17)0.72082 (7)0.0463 (3)
N30.33824 (17)0.28617 (16)0.59100 (8)0.0469 (3)
O10.2663 (3)0.24031 (19)0.54180 (9)0.0862 (5)
O20.42204 (19)0.18615 (16)0.65005 (8)0.0689 (3)
C110.77659 (16)0.77408 (16)0.98570 (7)0.0358 (3)
C120.71532 (16)0.68123 (16)1.04771 (7)0.0357 (3)
C130.64456 (19)0.75454 (19)1.12190 (8)0.0444 (3)
H130.60600.69151.16210.053*
C140.6294 (2)0.9241 (2)1.13810 (10)0.0543 (4)
H140.58040.97181.18880.065*
C150.6852 (2)1.0194 (2)1.08103 (10)0.0541 (4)
H150.67411.13171.09220.065*
C160.75989 (19)0.94553 (17)1.00491 (9)0.0437 (3)
C170.8334 (2)1.0005 (2)0.93490 (10)0.0543 (4)
H170.84411.10720.92650.065*
C180.9745 (2)0.8661 (3)0.80039 (10)0.0671 (5)
H18A1.07080.74050.79240.081*
H18B1.03480.94210.79800.081*
C190.8404 (2)0.9320 (2)0.73243 (10)0.0573 (4)
H190.73561.04800.73440.069*
C200.8612 (3)0.8364 (3)0.67013 (12)0.0725 (5)
H20A0.96470.71990.66650.087*
H20B0.77260.88480.62940.087*
N40.85309 (16)0.72904 (16)0.90988 (7)0.0434 (3)
N50.88521 (17)0.87130 (18)0.88237 (8)0.0505 (3)
N60.72571 (15)0.50676 (15)1.03441 (7)0.0415 (2)
O30.78980 (18)0.43963 (15)0.96842 (7)0.0602 (3)
O40.67488 (19)0.43012 (16)1.09090 (8)0.0691 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0349 (5)0.0344 (5)0.0368 (6)0.0177 (5)0.0018 (4)0.0023 (4)
C20.0381 (6)0.0340 (5)0.0391 (6)0.0191 (5)0.0006 (5)0.0028 (5)
C30.0472 (7)0.0438 (7)0.0408 (6)0.0213 (6)0.0050 (5)0.0044 (5)
C40.0571 (8)0.0405 (7)0.0450 (7)0.0172 (6)0.0076 (6)0.0049 (5)
C50.0575 (8)0.0323 (6)0.0537 (8)0.0198 (6)0.0006 (6)0.0000 (5)
C60.0429 (6)0.0349 (6)0.0467 (7)0.0207 (5)0.0035 (5)0.0073 (5)
C70.0499 (7)0.0449 (7)0.0560 (8)0.0275 (6)0.0010 (6)0.0124 (6)
C80.0510 (8)0.0786 (10)0.0469 (8)0.0337 (8)0.0057 (6)0.0141 (7)
C90.0516 (8)0.0773 (11)0.0546 (9)0.0345 (8)0.0082 (7)0.0023 (8)
C100.0568 (9)0.0864 (13)0.0607 (10)0.0308 (9)0.0006 (8)0.0034 (9)
N10.0444 (6)0.0458 (6)0.0413 (6)0.0250 (5)0.0048 (4)0.0006 (5)
N20.0453 (6)0.0548 (7)0.0453 (6)0.0280 (5)0.0021 (5)0.0107 (5)
N30.0516 (6)0.0404 (6)0.0563 (7)0.0284 (5)0.0044 (5)0.0006 (5)
O10.1353 (13)0.0694 (8)0.0879 (9)0.0731 (9)0.0361 (9)0.0031 (7)
O20.0785 (8)0.0473 (6)0.0881 (9)0.0373 (6)0.0305 (7)0.0222 (6)
C110.0350 (5)0.0359 (6)0.0385 (6)0.0185 (5)0.0107 (4)0.0035 (5)
C120.0354 (6)0.0328 (5)0.0394 (6)0.0171 (5)0.0079 (5)0.0029 (4)
C130.0454 (7)0.0467 (7)0.0396 (6)0.0214 (6)0.0047 (5)0.0012 (5)
C140.0592 (8)0.0515 (8)0.0484 (8)0.0214 (7)0.0056 (6)0.0131 (6)
C150.0601 (9)0.0393 (7)0.0652 (9)0.0229 (6)0.0165 (7)0.0084 (6)
C160.0457 (7)0.0371 (6)0.0532 (7)0.0236 (5)0.0165 (6)0.0061 (5)
C170.0574 (8)0.0509 (8)0.0655 (9)0.0363 (7)0.0199 (7)0.0172 (7)
C180.0548 (9)0.0939 (13)0.0546 (9)0.0423 (9)0.0056 (7)0.0238 (9)
C190.0529 (8)0.0657 (9)0.0513 (8)0.0303 (7)0.0036 (6)0.0144 (7)
C200.0687 (11)0.0900 (13)0.0579 (10)0.0402 (10)0.0091 (8)0.0004 (9)
N40.0441 (6)0.0490 (6)0.0400 (5)0.0257 (5)0.0059 (4)0.0048 (5)
N50.0500 (6)0.0615 (7)0.0476 (6)0.0354 (6)0.0112 (5)0.0162 (5)
N60.0421 (5)0.0377 (5)0.0482 (6)0.0223 (5)0.0070 (5)0.0026 (4)
O30.0892 (8)0.0508 (6)0.0500 (6)0.0399 (6)0.0076 (5)0.0067 (5)
O40.0824 (8)0.0530 (6)0.0815 (8)0.0439 (6)0.0186 (7)0.0003 (6)
Geometric parameters (Å, º) top
C1—N11.3459 (17)C11—N41.3459 (16)
C1—C21.4208 (17)C11—C121.4196 (17)
C1—C61.4337 (17)C11—C161.4313 (17)
C2—C31.3648 (18)C12—C131.3686 (18)
C2—N31.4517 (16)C12—N61.4509 (16)
C3—C41.409 (2)C13—C141.407 (2)
C3—H30.9300C13—H130.9300
C4—C51.358 (2)C14—C151.358 (2)
C4—H40.9300C14—H140.9300
C5—C61.402 (2)C15—C161.403 (2)
C5—H50.9300C15—H150.9300
C6—C71.389 (2)C16—C171.391 (2)
C7—N21.330 (2)C17—N51.326 (2)
C7—H70.9300C17—H170.9300
C8—N21.4649 (19)C18—N51.469 (2)
C8—C91.489 (2)C18—C191.486 (2)
C8—H8A0.9700C18—H18A0.9700
C8—H8B0.9700C18—H18B0.9700
C9—C101.279 (2)C19—C201.304 (3)
C9—H90.9300C19—H190.9300
C10—H10A0.9300C20—H20A0.9300
C10—H10B0.9300C20—H20B0.9300
N1—N21.3615 (16)N4—N51.3605 (16)
N3—O21.2137 (16)N6—O31.2240 (15)
N3—O11.2207 (17)N6—O41.2292 (15)
N1—C1—C2131.9 (2)N4—C11—C12131.5 (2)
N1—C1—C6111.6 (2)N4—C11—C16111.7 (2)
C2—C1—C6116.5 (2)C12—C11—C16116.8 (2)
C3—C2—C1120.6 (2)C13—C12—C11120.6 (2)
C3—C2—N3118.2 (2)C13—C12—N6118.2 (2)
C1—C2—N3121.3 (2)C11—C12—N6121.2 (2)
C2—C3—C4121.2 (2)C12—C13—C14120.8 (2)
C2—C3—H3119.4C12—C13—H13119.6
C4—C3—H3119.4C14—C13—H13119.6
C5—C4—C3120.8 (2)C15—C14—C13121.2 (2)
C5—C4—H4119.6C15—C14—H14119.4
C3—C4—H4119.6C13—C14—H14119.4
C4—C5—C6118.9 (2)C14—C15—C16118.8 (2)
C4—C5—H5120.6C14—C15—H15120.6
C6—C5—H5120.6C16—C15—H15120.6
C7—C6—C5134.0 (2)C17—C16—C15134.4 (2)
C7—C6—C1104.0 (2)C17—C16—C11103.8 (2)
C5—C6—C1121.9 (2)C15—C16—C11121.8 (2)
N2—C7—C6106.6 (2)N5—C17—C16106.7 (2)
N2—C7—H7126.7N5—C17—H17126.6
C6—C7—H7126.7C16—C17—H17126.6
N2—C8—C9114.9 (2)N5—C18—C19113.1 (2)
N2—C8—H8A108.5N5—C18—H18A109.0
C9—C8—H8A108.5C19—C18—H18A109.0
N2—C8—H8B108.5N5—C18—H18B109.0
C9—C8—H8B108.5C19—C18—H18B109.0
H8A—C8—H8B107.5H18A—C18—H18B107.8
C10—C9—C8127.5 (2)C20—C19—C18123.8 (2)
C10—C9—H9116.3C20—C19—H19118.1
C8—C9—H9116.3C18—C19—H19118.1
C9—C10—H10A120.0C19—C20—H20A120.0
C9—C10—H10B120.0C19—C20—H20B120.0
H10A—C10—H10B120.0H20A—C20—H20B120.0
C1—N1—N2103.1 (2)C11—N4—N5103.0 (2)
C7—N2—N1114.7 (2)C17—N5—N4114.8 (2)
C7—N2—C8126.3 (2)C17—N5—C18126.9 (2)
N1—N2—C8119.0 (2)N4—N5—C18118.3 (2)
O2—N3—O1122.8 (2)O3—N6—O4122.8 (2)
O2—N3—C2118.7 (2)O3—N6—C12118.6 (2)
O1—N3—C2118.5 (2)O4—N6—C12118.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···N20.932.602.907 (3)100
C5—H5···O1i0.932.493.4004 (19)165
C8—H8A···O4ii0.972.453.205 (2)134
C15—H15···O4i0.932.493.3986 (19)167
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···N20.932.602.907 (3)100
C5—H5···O1i0.932.493.4004 (19)165
C8—H8A···O4ii0.972.453.205 (2)134
C15—H15···O4i0.932.493.3986 (19)167
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+2.
 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

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Volume 69| Part 11| November 2013| Pages o1603-o1604
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